SPEED CONTROLLER FOR INVERTER

摘要

PURPOSE:To compensate the influence of a load even in a voltage inverter of open-loop control by detecting the load torque of an induction motor from the detection of the current of the inverter and controlling slip frequency and output voltage. CONSTITUTION:The current of an inverter is detected by a current detector 4 and a current detecting circuit 5. Current-induction motor torque conversion is conducted by a conversion section 6. A motor torque signal is converted into a torque boost set value by a setting conversion section 7. A command value from a voltage command section 8 and the torque boost set value are added by an addition section 9, and applied to an output-voltage control section 10 for an inverter. A frequency command signal is input to an arithmetic section 11 besides an output signal from the voltage control section 10, and PWM arithmetic processing is executed.